{"id":177756,"date":"2022-04-20T00:17:56","date_gmt":"2022-04-19T16:17:56","guid":{"rendered":"http:\/\/www.idc.net\/help\/177756\/"},"modified":"2022-04-20T00:17:56","modified_gmt":"2022-04-19T16:17:56","slug":"%e5%90%8e%e6%b5%aa%e4%ba%91python%e6%95%99%e7%a8%8b%ef%bc%9apython%e5%9e%83%e5%9c%be%e5%9b%9e%e6%94%b6%e6%9c%ba%e5%88%b6%e6%98%af%e4%bb%80%e4%b9%88","status":"publish","type":"post","link":"https:\/\/idc.net\/help\/177756\/","title":{"rendered":"\u540e\u6d6a\u4e91Python\u6559\u7a0b\uff1aPython\u5783\u573e\u56de\u6536\u673a\u5236\u662f\u4ec0\u4e48"},"content":{"rendered":"

<\/p>\n

\u4e0d\u540c\u4e8eC\/C++\uff0c\u50cfPython\u8fd9\u6837\u7684\u8bed\u8a00\u662f\u4e0d\u9700\u8981\u7a0b\u5e8f\u5458\u5199\u4ee3\u7801\u6765\u7ba1\u7406\u5185\u5b58\u7684\uff0c\u5b83\u7684GC(Garbage Collection)\u673a\u5236 \u5b9e\u73b0\u4e86\u81ea\u52a8\u5185\u5b58\u7ba1\u7406\u3002GC\u505a\u7684\u4e8b\u60c5\u5c31\u662f\u89e3\u653e\u7a0b\u5e8f\u5458\u7684\u53cc\u624b\uff0c\u627e\u51fa\u5185\u5b58\u4e2d\u4e0d\u7528\u7684\u8d44\u6e90\u5e76\u91ca\u653e\u8fd9\u5757\u5185\u5b58\u3002 \u4e0b\u9762\u6211\u4eec\u6765\u770b\u770bPython\u7684GC\u662f\u600e\u4e48\u505a\u7684\uff1a<\/p>\n

Python\u81ea\u5e26\u7684\u89e3\u91ca\u5668CPython\u4e3b\u8981\u4f7f\u7528\u4e86\u4e09\u79cd\u5783\u573e\u56de\u6536\u673a\u5236(\u5f15\u7528\u8ba1\u6570\u4e3a\u4e3b\uff0c\u6807\u8bb0-\u6e05\u9664\u548c\u5206\u4ee3\u56de\u6536\u4e3a\u8f85)\uff1a<\/p>\n

\u5f15\u7528\u8ba1\u6570<\/strong><\/p>\n

\u6807\u8bb0\u6e05\u9664<\/strong><\/p>\n

\u5206\u4ee3\u56de\u6536<\/strong><\/p>\n

\u4e0b\u9762\u8ba9\u6211\u4eec\u5206\u522b\u4e86\u89e3\u4e0b\u8fd9\u51e0\u79cd\u673a\u5236\uff1a<\/p>\n

\u5f15\u7528\u8ba1\u6570<\/p>\n

\u5f15\u7528\u8ba1\u6570\u6cd5Reference Counting\u7684\u539f\u7406\u662f\uff0c\u6bcf\u4e2a\u5bf9\u8c61\u90fd\u7ef4\u62a4\u4e00\u4e2a\u5f15\u7528\u8ba1\u6570\u5b57\u6bb5\uff0c\u8bb0\u5f55\u8fd9\u4e2a\u5bf9\u8c61\u88ab\u5f15\u7528\u7684\u6b21\u6570(\u5982\u679c\u4e0d\u6e05\u695a\u53d8\u91cf->\u5f15\u7528->\u5bf9\u8c61 \u7684\u95ee\u9898\uff0c\u53ef\u4ee5\u67e5\u770b\u8fd9\u7bc7\u6587\u7ae0Python\u7684\u6df1\u62f7\u8d1d\u548c\u6d45\u62f7\u8d1d),\u5982\u679c\u6709\u65b0\u7684\u5f15\u7528\u6307\u5411\u5bf9\u8c61\uff0c\u5bf9\u8c61\u5f15\u7528\u8ba1\u6570\u5c31\u52a0\u4e00\uff0c\u5f15\u7528\u88ab\u9500\u6bc1\u65f6\uff0c\u5bf9\u8c61\u5f15\u7528\u8ba1\u6570\u51cf\u4e00\uff0c\u5f53\u7528\u6237\u7684\u5f15\u7528\u8ba1\u6570\u4e3a0\u65f6\uff0c\u8be5\u5185\u5b58\u88ab\u91ca\u653e\u3002\u53ef\u4ee5\u901a\u8fc7sys.getrefcount()\u51fd\u6570\u67e5\u770b\u5bf9\u8c61\u88ab\u5f15\u7528\u7684\u4e2a\u6570\u3002<\/p>\n

\u8fd9\u79cd\u65b9\u6cd5\u4e3b\u8981\u5b58\u5728\u4e24\u79cd\u95ee\u9898\uff1a<\/p>\n

\u9700\u8981\u53bb\u7ef4\u62a4\u5f15\u7528\u8ba1\u6570\uff0c\u5b58\u5728\u6267\u884c\u6548\u7387\u95ee\u9898<\/p>\n

\u65e0\u6cd5\u89e3\u51b3\u5faa\u73af\u5f15\u7528\u95ee\u9898<\/p>\n

\u6240\u8c13\u5faa\u73af\u5f15\u7528\u5c31\u662f\uff1a\u6709\u4e00\u7ec4\u5bf9\u8c61\u7684\u5f15\u7528\u8ba1\u6570\u4e0d\u4e3a0\uff0c\u4f46\u662f\u8fd9\u7ec4\u5bf9\u8c61\u5b9e\u9645\u4e0a\u5e76\u6ca1\u6709\u88ab\u53d8\u91cf\u5f15\u7528\uff0c\u5b83\u4eec\u4e4b\u95f4\u662f\u76f8\u4e92\u5f15\u7528\uff0c\u800c\u4e14\u4e5f\u4e0d\u4f1a\u6709\u5176\u4ed6\u7684\u53d8\u91cf\u518d\u53bb\u5f15\u7528\u8fd9\u7ec4\u5bf9\u8c61\uff0c\u6700\u7ec8\u5bfc\u81f4\u5982\u679c\u4f7f\u7528 \u5f15\u7528\u8ba1\u6570\u6cd5 \u8fd9\u4e9b\u5bf9\u8c61\u5360\u7528\u7684\u5185\u5b58\u6c38\u8fdc\u4e0d\u4f1a\u88ab\u91ca\u653e\u3002<\/p>\n

\u5199\u4e00\u6bb5\u4ee3\u7801\u4e3e\u4e2a\u4f8b\u5b50\uff1a<\/p>\n

In [23]: a = []\n\nIn [24]: b = []\n\nIn [25]: a.append(b)\n\nIn [26]: b.append(a)\n\nIn [27]: a\nOut[27]: [[[...]]]\n\nIn [28]: b\nOut[28]: [[[...]]]<\/pre>\n
\u53ef\u4ee5\u770b\u5230\uff0c\u73b0\u5728a b\u90fd\u51fa\u73b0\u4e86\u5faa\u73af\u5f15\u7528\uff0c\u6b64\u65f6\u5c31\u7b97\u4f7f\u7528del\u8bed\u53e5\u5220\u9664\u53d8\u91cf\uff0c\u88ab\u4f7f\u7528\u7684\u5185\u5b58\u4e5f\u4e0d\u4f1a\u88ab\u56de\u6536\uff0c\u6240\u4ee5\u5c31\u9700\u8981\u7b2c\u4e8c\u79cdGC\u673a\u5236\uff1a<\/p>\n
\u6807\u8bb0\u6e05\u9664<\/p>\n
\u6807\u8bb0\u6e05\u9664Mark-Sweep\u662f\u9488\u5bf9\u5faa\u73af\u5f15\u7528\u95ee\u9898\u7684\u56de\u6536\u673a\u5236\uff0c\u4f5c\u7528\u7684\u5bf9\u8c61\u662f\u5bb9\u5668\u7c7b\u578b\u7684\u5bf9\u8c61(\u6bd4\u5982\uff1alist\u3001set\u3001dict\u7b49)\u3002<\/p>\n
\u539f\u7406\u662f\uff1a\u901a\u8fc7\u6839\u8282\u70b9\u5bf9\u8c61(\u4e0d\u4f1a\u88ab\u5220\u9664\u7684\u5bf9\u8c61)\u5bf9\u6709\u5411\u56fe\u628a\u6240\u6709\u6d3b\u52a8\u5bf9\u8c61\u6253\u4e0a\u6807\u8bb0\uff0c\u7136\u540e\u56de\u6536\u6ca1\u6709\u88ab\u6807\u8bb0\u7684\u975e\u6d3b\u52a8\u5bf9\u8c61\u3002<\/p>\n
\u5206\u4ee3\u56de\u6536<\/p>\n
\u5206\u4ee3\u56de\u6536\u662f\u5efa\u7acb\u5728\u6807\u8bb0\u6e05\u9664\u57fa\u7840\u4e0a\u7684\u4e00\u79cd\u8f85\u52a9\u56de\u6536\u5bb9\u5668\u5bf9\u8c61\u7684GC\u673a\u5236\u3002 \u65e0\u8bba\u5f00\u53d1\u7684\u7a0b\u5e8f\u7c7b\u578b\u5982\u4f55\uff0c\u89c4\u6a21\u5982\u4f55\uff0c\u90fd\u6709\u8fd9\u6837\u7684\u76f8\u540c\u4e4b\u5904\uff1a\u4e00\u4e9b\u6bd4\u4f8b\u7684\u5185\u5b58\u751f\u5b58\u5468\u671f\u90fd\u5f88\u77ed\uff0c\u800c\u53e6\u4e00\u4e9b\u5185\u5b58\u7684\u751f\u5b58\u5468\u671f\u6bd4\u8f83\u957f\uff0c\u53ef\u80fd\u4f1a\u4f34\u968f\u7740\u6574\u4e2a\u7a0b\u5e8f\u7684\u5f00\u59cb\u548c\u7ed3\u675f\u3002 \u6240\u4ee5\u5206\u4ee3\u56de\u6536\u5c31\u6839\u636e\u7cfb\u7edf\u4e2d\u5185\u5b58\u5b58\u6d3b\u65f6\u95f4\u628a\u5b83\u4eec\u5212\u5206\u6210\u4e0d\u540c\u7684\u96c6\u5408\uff1a\u4e00\u5171\u5206\u6210\u4e09\u4e2a\u96c6\u5408\uff0c\u6bcf\u4e2a\u96c6\u5408\u79f0\u4e3a\u4e00\u4e2a\u4ee3\u3002 \u5b83\u4eec\u7684\u5783\u573e\u6536\u96c6\u9891\u7387 \u968f \u5bf9\u8c61 \u5b58\u6d3b\u5b58\u6d3b\u65f6\u95f4\u7684\u589e\u5927 \u800c \u51cf\u5c0f\u3002\u4e5f\u5c31\u662f\u8bf4\uff1a\u5bf9\u4e8e\u5b58\u6d3b\u65f6\u95f4\u8d8a\u957f\u7684\u5bf9\u8c61\uff0c\u5c31\u8d8a\u4e0d\u53ef\u80fd\u662f\u5783\u573e\uff0c\u51cf\u5c11\u5bf9\u5176\u7684\u6536\u96c6\u9891\u7387\u3002\u800c\u65b0\u521b\u5efa\u7684\u5bf9\u8c61\u90fd\u5728\u7b2c\u4e00\u4ee3\uff0c\u7b2c\u4e00\u4ee3\u96c6\u5408\u603b\u6570\u8fbe\u5230\u4e0a\u9650\u540e\uff0c\u4f1a\u89e6\u53d1GC\u673a\u5236\uff1a\u53ef\u4ee5\u56de\u6536\u7684\u5bf9\u8c61\u6240\u5360\u7684\u5185\u5b58\u88ab\u91ca\u653e\uff0c\u4e0d\u80fd\u88ab\u56de\u6536\u7684\u79fb\u5230\u4e2d\u5e74\u4ee3\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u4e0d\u540c\u4e8eC\/C++\uff0c\u50cfPython\u8fd9\u6837\u7684\u8bed\u8a00\u662f\u4e0d\u9700\u8981\u7a0b\u5e8f\u5458\u5199\u4ee3\u7801\u6765\u7ba1\u7406\u5185\u5b58\u7684\uff0c\u5b83\u7684GC(Garbage Coll […]<\/p>\n","protected":false},"author":1,"featured_media":177757,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[182397],"tags":[],"class_list":["post-177756","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-python"],"_links":{"self":[{"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/posts\/177756","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/comments?post=177756"}],"version-history":[{"count":0,"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/posts\/177756\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/media\/177757"}],"wp:attachment":[{"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/media?parent=177756"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/categories?post=177756"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/idc.net\/help\/wp-json\/wp\/v2\/tags?post=177756"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}